Regular people like us (we're assuming you're a lot like us ear-wise) have asymmetric ears so an asymmetric bud like Asym fits like nobody's business (an idiom meaning great). Its flush fit and wrapped cable position means you can run on the treadmill or do your Flashdance dance and they'll stay put. Asym also fits perfectly under beanies and helmets (for those doing the really sketchy stuff).